I'm a beginner orchid grower & have a phal orchid I've had for 1 year, it came in bark, It's roots are coming out the bottom of the pot. I'm wanting to repot it & repot some clearance rack orchids(also phals) I recently bought (I removed them from the sphagnum moss they were packed in & have the roots in the air for now after trimming off the damaged rotted roots) since the orchid I first got has done well in bark, I want to use that. How often to repot orchids in bark every year or every year and half? Also I know nothing about mixing my own mixes so are there any good orchid mixes sold in the stores?

I personally like Gubler's Orchid Mix. The fir bark looks nice and fresh when I bought them. They're kinda stingy on the sponge rock though. This one is easy to get at The Home Depot right now. You don't have to get this brand. I just brought it up 'cause I liked it.

You don't need the sponge rock, btw. I've grown Phalaenopsis in straight up medium to large grade bark before, and still do, actually - they do fine.

Easy, nothing terribly special.

I'd change them out at the 1 1/2 to 2 yr mark. Just see how fast the media breaks down.

The mix that will work best for you depends on your growing environment and your culture habits. If bark has worked well for you so far, I would keep using it. I don't believe in trying to fix something that isn't broken. I try to repot my phals once a year in hot, humid South Florida, but I've gone as long as two years without any problems. My only recommendation is to use the smallest pot that the roots will comfortably fit in. Using a pot that's too big can lead to dead spots in the mix that stay too wet and lead to root rot.

Two of the rescue orchids had such damaged roots, that the roots that were left are so little that the pot size they would fit in would be too small to even support the orchid. Should I keep them in the air without repotting them, or let them sit on top of the bark, using the bamboo skewers that held the bloom spikes to support them?

I looove the Gubler's medium bark mix! The bark chips are bigger than I have seen in other brands - great if you are like me and always rot Phal roots, also great for Catts and others that like to dry out more quickly. (I also love the fine mix for finer rooted orchids)

That said, I usually just get the bark chips and add whatever else... but I will splurge on the Gublers mix for Phals, some Catts, Laelias, a few others, just because the bark is so nice and chunky!